Mastless wind turbine with stationary sails for improved power generation

ABSTRACT

Aspects of the disclosure disclose a turbine that includes multiple rotating sails and multiple stationary sails. A mastless vertical axis wind turbine includes a first plurality of sails that are configured to rotate about a vertical axis under the influence of wind. A platform is coupled to the first plurality of sails. During operation of the mastless vertical axis wind turbine, the platform is in tension with the first plurality of sails at one or more points about a particular end of the first plurality of the sails. The mastless vertical axis wind turbine also includes a second plurality of sails having respective first ends that are coupled together and second ends that are each coupled to one or more stationary surfaces. The second plurality of sails are configured to remain stationary as the first plurality of sails rotate under the influence of the wind.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation-in-part of U.S. patent applicationSer. No. 17/321,271 filed May 14, 2021 and entitled “MASTLESS WINDTURBINE FOR POWER GENERATION”; which is a continuation of U.S. patentapplication Ser. No. 15/901,701 filed Feb. 21, 2018, that issued as U.S.Pat. No. 11,009,004 on May 18, 2021, and entitled “MASTLESS WIND TURBINEFOR POWER GENERATION”; which is a continuation of U.S. patentapplication Ser. No. 15/368,303 filed Dec. 2, 2016, that issued as U.S.Pat. No. 9,995,275 on Jun. 12, 2018, and entitled “MASTLESS WIND TURBINEFOR POWER GENERATION”; which claims the benefit of U.S. ProvisionalPatent Application No. 62/237,076 filed Oct. 5, 2015, and entitled,“WIND TURBINES AND OTHER TURBINES FOR POWER GENERATION”, the disclosuresof which are hereby incorporated herein by reference in their entirety.

TECHNICAL FIELD

The present application is generally related to wind turbines. Inparticular, but not by way of limitation, the present application isrelated to mastless wind turbines having sails that rotate under theinfluence of wind and sails that do not rotate while the other sailsrotate under the influence of the wind.

BACKGROUND

Commonly used wind turbines, particularly those that rotate about avertical axis, are mechanically inefficient, cumbersome, and relativelyexpensive. A contributing factor to these difficulties is the fact thatknown wind turbines that rotate about a vertical axis rely upon acentral mast extending upward from the bottom of the turbine to anchorrotating vanes. During operation, the central mast rotates with vanes towhich it is attached. Including such a mast not only increases cost andweight of required material, but also induces mechanical problems.Torsional forces between the vanes, the mast, and bottom surface giverise to mechanical inefficiencies and breakdown. As such, known windturbines of these types are difficult to deploy and maintain energyoutput, particularly under varying wind conditions.

Further, known vertical axis wind turbines utilize blades and/or wheelsthat can be heavy, unsightly, dangerous to wildlife, and difficult totransport. Rotation of the heavy blades and/or wheels can cause damageto surrounding objects, such as animals, as well as the blades and/orwheels themselves.

To increase the energy output of turbines, multistage horizontalturbines have been developed. These multistage turbines, such as thoseused in jet engines, include stages of rotors alternated with stages ofstators. The stators are positioned and configured to direct the airflowin a desired direction. Although energy output of multistage turbines ishigher than single stage turbines, the multistage turbines includesignificant extra costs for materials and increase the weight of theturbines, which makes the turbines less suitable for deployment forcapturing wind energy. The increased costs and complexity of thesedesigns do not improve the energy output enough to justify thedeployment from a cost perspective. For example, the addition of a partor feature may be evaluated in terms of the contribution to the returnon investment of original machine. In the case of a wind turbine, anaddition of multiple stages or other features may be economicallyefficient if the improvement increases the output power of the turbineby a factor that is greater than the increased cost factor of making theaddition. To illustrate, adding multiple stages to a turbine thatincrease cost by 20% may not be economically feasible if the outputpower is only increased by 10%.

BRIEF SUMMARY

In various aspects, a turbine may be utilized to generate energy. Theturbine can include a frame, base, and sails. One or more sails can becoupled at an end to the base. One or more of the sails can be coupledto a frame. As the sails rotate, power can be generated. Implementationscan include one or more of the following features: the frame can beexternal. The frame can be shaped approximately as a triangular pyramid.The turbine can include six (6) sails. The base can include an openframe with a hexagonal hub and 6 spokes.

According to certain aspects, a mastless turbine comprises a pluralityof sails that rotate about a vertical axis under the influence of wind.The turbine also comprises a bottom platform configured to couple theplurality of sails to a first stationary support. During operation ofthe mastless vertical axis wind turbine, the bottom platform connects toand is in tension with the plurality of sails at one or more pointsabout the bottom of the plurality of the sails and rotates with theplurality of sails under the influence of wind. The turbine furthercomprises a connector that is configured to couple the plurality ofsails to a second stationary support. During operation of the mastlessvertical axis wind turbine, the connector connects to and is in tensionwith the plurality of sails about the axis of rotation and the top ofthe plurality of the sails. The central connector itself comprises a topportion configured to attach to the second stationary support thatduring operation of the mastless vertical axis wind turbine does notrotate. The central connector also comprises a bottom portion configuredto attach to the plurality of the sails that during operation of themastless vertical axis wind turbine rotates with respect to the topportion with the plurality of sails under the influence of wind.

In some implementations, the turbine may be configured with one or morestationary sails (e.g., stators) to at least partially re-direct airflowto the rotating sails of the turbine, thereby improving energy output ofthe turbine. To illustrate, a mastless vertical axis wind turbine mayinclude a platform and at least two types of sails: moving (e.g.,rotating) sails and stationary sails (e.g., stators). For example, afirst plurality of sails may be coupled to the platform and configuredto rotate about a vertical axis under the influence of wind. Duringoperation of the mastless vertical axis wind turbine, the platform maybe configured to be in tension with the first plurality of sails at oneor more points about a particular end (e.g., the bottom) of the firstplurality of the sails. The mastless vertical axis wind turbine may becoupled to a battery that is configured to store power generated by therotation of the first plurality of sails, or the turbine may act as apower source for one or more other components. A second plurality ofsails that are disposed outside a sweeping range of the first pluralityof sails may be coupled together at respective first ends (e.g., thetop) above the first plurality of sails on the vertical axis. The secondplurality of sails may have second ends (e.g., the bottoms) that areeach coupled to one or more stationary surfaces, such as the ground, abase, or the like. The second plurality of sails may be configured toremain stationary as the first plurality of sails rotate under theinfluence of the wind during operation of the mastless vertical axiswind turbine. By appropriate positioning and configuration of the secondplurality of sails, airflow that would otherwise flow away from thefirst plurality of sails may be redirected to the first plurality ofsails, which may increase swept area of the rotating sails, increasepositive drive pressure on downwind rotating sails, and decreaseparasitic drag pressure on upwind rotating sails. These effects mayincrease energy production of the mastless vertical axis wind turbine bymore than 20%, in some implementations, as compared to a vertical axisturbine without the stationary sails.

According to one aspect, a mastless vertical axis wind turbine isdescribed. The mastless vertical axis wind turbine includes a firstplurality of sails configured to, during operation of the mastlessvertical axis wind turbine, rotate about a vertical axis under theinfluence of wind. The mastless vertical axis wind turbine also includesa platform coupled to the first plurality of sails and configured to,during operation of the mastless vertical axis wind turbine, be intension with the first plurality of sails at one or more points about aparticular end of the first plurality of sails. The mastless verticalaxis wind turbine further includes a second plurality of sails havingrespective first ends that are coupled together and second ends that areeach coupled to one or more stationary surfaces. The second plurality ofsails are configured to remain stationary as the first plurality ofsails rotate under the influence of the wind.

According to another aspect, a method for generating energy with amastless vertical axis wind turbine is described. The method includesconfiguring a first plurality of sails that during operation of themastless vertical axis wind turbine rotate about a vertical axis underthe influence of wind. The method also includes supporting the firstplurality of sails utilizing a platform that during operation of themastless vertical axis wind turbine is connected to and in tension withthe first plurality of sails at one or more points about a particularend of first the plurality of the sails. The method further includesconfiguring a second plurality of sails that during operation of themastless vertical axis wind turbine remain stationary as the firstplurality of sails rotate under the influence of the wind. The secondplurality of sails have respective first ends that are coupled togetherand second ends that are each coupled to one or more stationarysurfaces.

According to another aspect, a mastless vertical axis wind turbine isdescribed. The mastless vertical axis wind turbine includes a firstplurality of sails configured to, during operation of the mastlessvertical axis wind turbine, rotate about a vertical axis under theinfluence of wind. The mastless vertical axis wind turbine also includesa platform configured to couple the first plurality of sails to a firststationary support. The platform is configured to, during operation ofthe mastless vertical axis wind turbine, be in tension with the firstplurality of sails at one or more points about a first end of the firstplurality of sails and to rotate with the first plurality of sails underthe influence of the wind. The first stationary support is configured toremain stationary as the first plurality of sails rotate under theinfluence of the wind. The mastless vertical axis wind turbine includesa second plurality of sails having respective first ends that arecoupled together and second ends that are each coupled to one or morestationary surfaces. The second plurality of sails are configured toremain stationary while the first plurality of sails rotate under theinfluence of the wind. The mastless vertical axis wind turbine furtherincludes a central connector configured to couple the first plurality ofsails and the second plurality of sails to a second stationary support.The central connector is configured to, during operation of the mastlessvertical axis wind turbine, be in tension with the first plurality ofsails about the vertical axis and a second end of the first plurality ofsails.

According to another aspect, a method for generating energy with amastless vertical axis wind turbine is described. The method includesengaging the mastless vertical axis wind turbine with a first stationarysupport and a second stationary support. The mastless vertical axis windturbine includes a first plurality of sails that rotate about a verticalaxis under the influence of wind. The mastless vertical axis windturbine also includes a platform configured to couple the firstplurality of sails to the first stationary support. The platform isconfigured to, during operation of the mastless vertical axis windturbine, be in tension with the first plurality of sails at one or morepoints about a first end of the first plurality of sails and to rotatewith the first plurality of sails under the influence of the wind whilethe first stationary support remains stationary. The mastless verticalaxis wind turbine further includes a central connector configured tocouple the first plurality of sails to the second stationary support.The central connector is configured to, during operation of the mastlessvertical axis wind turbine, be in tension with the first plurality ofsails about the vertical axis and a second end of the first plurality ofsails. The method further includes engaging a second plurality of sailsto the central connector of the mastless vertical axis wind turbine. Thesecond plurality of sails have respective first ends that are coupledtogether and second ends that are each coupled to one or more stationarysurfaces. The second plurality of sails are configured to, duringoperation of the mastless vertical axis wind turbine, remain stationarywhile the first plurality of sails rotate under the influence of thewind.

The foregoing has outlined rather broadly the features and technicaladvantages of the present disclosure in order that the detaileddescription that follows may be better understood. Additional featuresand advantages will be described hereinafter which form the subject ofthe claims of the present disclosure. It should be appreciated by thoseskilled in the art that the conception and specific implementationsdisclosed may be readily utilized as a basis for modifying or designingother structures for carrying out the same purposes of the presentdisclosure. It should also be realized by those skilled in the art thatsuch equivalent constructions do not depart from the scope of thepresent disclosure as set forth in the appended claims. The novelfeatures which are disclosed herein, both as to organization and methodof operation, together with further objects and advantages will bebetter understood from the following description when considered inconnection with the accompanying figures. It is to be expresslyunderstood, however, that each of the figures is provided for thepurpose of illustration and description only and is not intended as adefinition of the limits of the present disclosure.

BRIEF DESCRIPTION OF THE DRAWINGS

For a more complete understanding of the present disclosure, referenceis now made to the following descriptions taken in conjunction with theaccompanying figures, in which:

FIG. 1A illustrates an example of a wind turbine according to one ormore aspects;

FIG. 1B illustrates a cross section portion of a wind turbine incommunication with an energy regulation mechanism according to one ormore aspects;

FIG. 1C illustrates a platform of a wind turbine according to one ormore aspects;

FIG. 1D illustrates aspects of an example of a wind turbine according toone or more aspects;

FIG. 2 illustrates aspects of an example of a wind turbine according toone or more aspects;

FIG. 3A illustrates aspects of a platform of a wind turbine according toone or more aspects;

FIG. 3B illustrates additional aspects of a platform of a wind turbineaccording to one or more aspects;

FIG. 3C illustrates additional aspects of a platform of a wind turbineaccording to one or more aspects;

FIG. 3D illustrates additional aspects of a platform of a wind turbineaccording to one or more aspects;

FIG. 3E illustrates additional aspects of a platform of a wind turbineaccording to one or more aspects;

FIG. 3F illustrates additional aspects of a platform of a wind turbineaccording to one or more aspects;

FIG. 3G illustrates additional aspects of a platform of a wind turbineaccording to one or more aspects;

FIG. 3H illustrates additional aspects of a platform of a wind turbineaccording to one or more aspects;

FIG. 4 illustrates an example of a wind turbine according to one or moreaspects;

FIG. 5A illustrates a front view of an example of a wind turbine withstators according to one or more aspects;

FIG. 5B illustrates a top-down view of the wind turbine with stators ofFIG. 5A;

FIG. 5C illustrates a front view of another example of a wind turbinewith stators according to one or more aspects;

FIG. 6 illustrates a flow chart of an example of a method for generatingenergy using a mastless vertical axis wind turbine according to one ormore aspects; and

FIG. 7 illustrates a flow chart of another example of a method forgenerating energy using a mastless vertical axis wind turbine accordingto one or more aspects.

It should be understood that the drawings are not necessarily to scaleand that the disclosed aspects are sometimes illustrateddiagrammatically and in partial views. In certain instances, detailswhich are not necessary for an understanding of the disclosed methodsand apparatuses or which render other details difficult to perceive mayhave been omitted. It should be understood, of course, that thisdisclosure is not limited to the particular aspects illustrated herein.

DETAILED DESCRIPTION

Aspects of the present application disclose a wind turbine that rotatesabout a vertical axis to generate energy under the influence of wind.The vanes or sails of the turbine are placed under tension by attachingthe bottom of each vane to a platform and the top of each vane to astructure or top tension point positioned about the center of the axisof rotation. The top tension point can comprise an external structurethat is supported around the turbine, or may comprise a top attachmentpoint. The latter is advantageous where, e.g., the turbine is reversiblyinstalled at various locations where an external support cannot beplaced about the turbine. In either case, as a result, the need for acentral mast is obviated.

In operation, the vanes converge toward the top of the turbine, i.e.,where each vane connects to the central structure or tension point attheir top edge. The configuration of the vanes can be changed byadjusting the position at which the vanes attach to the platform attheir bottom edge and the central top tension point.

As the turbine rotates, kinetic energy is generated and then convertedto electrical energy (e.g., via a generator), which can be utilized todrive machines (e.g., pumps, air compressors, motors, etc.) and/or canbe stored (e.g., in batteries, hydrogen (or other chemical form),high-pressure steam (or other physical form), and/or as compressed air,and the like). A turbine can be part of a turbine array and used inconjunction with an energy storage unit. To that end, an energy storageunit can be utilized in conjunction with one or more turbines in thearray and used to efficiently distribute energy to local or remotelocations.

Importantly, the energy storage unit can be utilized in conjunction withthe one or more turbines to produce a constant or near constant energyoutput over time and under varying conditions. That is, duringoperation, all or a portion of the energy generated by the one or moreturbines can be distributed to the energy storage unit. During periodsof low wind speed, and likewise, low turbine power output, the energystorage unit can be used to increase overall energy output to compensatefor a decrease in turbine energy output. During periods of high windspeed, and likewise, high turbine power output, the energy storage unitcan be used to buffer or accumulate energy to be provided during periodsof low wind speed, thereby enabling the turbine to be used to providepower, regardless of wind speed, without requiring additionaldispatchable energy sources.

In some implementations, a turbine described herein is configured withone or more stationary sails (e.g., stators) to at least partiallyre-direct airflow to rotating sails of the turbine. To illustrate, amastless vertical axis wind turbine may include a platform and at leasttwo types of sails: moving (e.g., rotating) sails and stationary sails(e.g., stators). The first sails (e.g., the rotating sails) may becoupled to the platform and configured to rotate about a vertical axisunder the influence of wind. The second sails (e.g., the stationarysails) may be disposed outside a sweeping range of the first sails andmay be coupled together above the first sails on the vertical axis. Thesecond sails may be configured to remain stationary as the first sailsrotate under the influence of the wind during operation of the mastlessvertical axis wind turbine, which may redirect airflow that wouldotherwise flow away from the first sails and thus increase swept area ofthe rotating sails (e.g., the first sails), increase positive drivepressure on downwind rotating sails, and decrease parasitic dragpressure on upwind rotating sails, as further described herein.

In view of the foregoing, described aspects provide a mastless verticalaxis wind turbine that comprises a plurality of sails that rotate abouta vertical axis under the influence of wind. A platform is connected toand in tension with the plurality of sails at one or more points aboutthe bottom of the plurality of the sails. Also, an external frame isconnected to and in tension with the plurality of sails at one or morepoints about the top of the plurality of the sails. The external frameitself comprises a plurality of legs that converge above the pluralityof sails at a central point about the vertical axis of rotation andextend beyond the path swept by the plurality of sails. Also, a couplingmechanism connects one or more of the plurality of legs to the pluralityof sails and is configured allow the plurality of sails to rotate aboutthe vertical axis of rotation while the plurality of legs remainstationary.

In some implementations, a generator is in communication with theplatform that generates energy in response to rotation of the platform.In some implementations, the generator is centrally aligned with thevertical axis of rotation and can be in communication with one or moreenergy storage units. To regulate energy output of the turbine over timeas discussed above, a controller can operate to cause the energy storageunits to increase energy output in response to a decrease in generatorenergy output and decrease energy output in response to an increase ingenerator energy output. Although referred to as a generator, in otheraspects the turbine can be configured to communicate with various typesof energy storage devices, such as generators, alternators, batteries orstorage cells, or the like, some of which may include downstreamelectrical circuitry for converting between alternating and directcurrent.

In some other implementations, a mastless vertical axis wind turbineincludes a first plurality of sails that are configured to rotate abouta vertical axis under the influence of wind. A platform is coupled tothe first plurality of sails. During operation of the mastless verticalaxis wind turbine, the platform is in tension with the first pluralityof sails at one or more points about a particular end of the firstplurality of the sails. The mastless vertical axis wind turbine alsoincludes a second plurality of sails having respective first ends thatare coupled together and second ends that are each coupled to one ormore stationary surfaces. The second plurality of sails are configuredto remain stationary as the first plurality of sails rotate under theinfluence of the wind.

FIG. 1A illustrates an example of turbine 100 according to one or moreaspects, FIG. 1B illustrates a cross section of a first portion ofturbine 100 illustrated in FIG. 1A, and FIG. 1C illustrates a platformor second portion of turbine 100 illustrated in FIG. 1A. Turbine 100 canbe used to generate energy (e.g., mechanical and/or electrical) from airflow. For example, turbine 100 can be positioned in an area and subjectto air flow (e.g., high wind speed and low wind speed).

Turbine 100 includes frame 110, rotating platform or base 120, and aplurality of vanes or sails 130. According to the illustratedembodiment, frame 110 is an external frame (e.g., external to sails 130)and operates to support and place tension on sails 130 in an upwarddirection. By placing sails 130 under sufficient tension using frame110, (1) sails 130 efficiently rotate in response to wind, and (2) theneed for a central mast attaching to sails 130 is eliminated. Also, asmentioned, according to another embodiment, tension may be placed onsails 130 by attaching each to a central point of tension that does notfurther comprise an external frame. In such embodiments, sails 130 canconnect to a central hook or the like where the hook is free to rotateat one end while it is held stationary at another end. This may beeffectuate through the use of bearings or the like, and is advantageouswhere turbine 100 is installed in compact locations where an externalframe would not fit.

Frame 110 can include any appropriate material to provide theappropriate strength to turbine 100. Frame 110 can at least partiallysupport sails 130 and/or base 120, and can be self-erecting and/ormanually erected (e.g., by a person).

In some embodiments, frame 110 includes at least three legs 112. Legs112 each have top end 114 and opposing bottom end 116 and legs 112 canbe positioned such that top ends 114 are disposed proximate each otherwhile bottom ends 116 are spaced from one another about thecircumference of the circle swept out by sails 130 and/or base 120.Therefore, the ends of legs 112 are uncoupled at or about a bottomportion of frame 110, and coupled (e.g., directly or indirectly) at orabout a top end of frame 110. For example, frame 110 can have three legs112 in a shape arranged as a triangular pyramid, where top end 114 ofeach leg 112 converges near the axis of rotation of sails 130 whilebottom ends 116 of each leg 112 are spaced from one another about thecircumference of the circle swept out by sails 130 and/or base 120.

In some embodiments, the ratio of a height of frame 110 to a width offrame 110 can be between approximately from 1-to-1 to 2-to-1, while in apreferred embodiment the ratio of the height of frame 110 to the widthof frame 110 is approximately 1.3 to approximately 1. However, it shouldbe appreciated that frame 110 can be any height, even much greater thanthat of rotating turbine 100 itself. An example might be to increase theground clearance of turbine 100 for any number of reasons.

Further, the size of frame 110 can be selected to allow sails 130 torotate within frame 110 without contacting legs 112. The ratio of theheight of frame 110 to the width of frame 110 can be approximately thesame as the ratio of the height of sail 130 to the width of sail 130,and the overall height of frame 110 can be larger than the overallheight of sail 130.

Platform or base 120 can include any appropriate material, such asmetal, fiber reinforced plastics, and/or wood. Preferably, to reduceweight of turbine 100, base 120 can comprise an open frame (e.g., atleast approximately 50% of the footprint of base 120 is open and/orcomponents of base 120 comprise an area of less than approximately 50%of the footprint of base 120).

Sails 130 can rotate in the presence of a fluid flow (e.g., wind) abouta central axis of rotation 102 to generate energy. Sails 130 can have ashape that is wider at bottom end 132 than at top end 134 where, e.g.,sails 130 can be approximately triangularly-shaped or approximatelytrapezoidally-shaped. When sails 130 are positioned in turbine 100,exterior side 136 of sails 130 can form an approximately conical shapeand/or at least a portion of a conical shape. In some embodiments, theratio of a height of a sail 130 to a width of a sail 130 can beapproximately 2-to-1. In a preferred embodiment, the ratio of the heightof turbine 100 to the width of turbine 100 can be approximately 1.3 toapproximately 1.

Turbine 100 can include an even or odd number of sails 130, where eachmay be formed of any appropriate material. In some embodiments, sails130 can include a material that allows each sail 130 to collapse, berolled, and/or otherwise reduced in size for storage, transport, and/orother appropriate reasons (e.g., winds exceeding a predetermined maximumvelocity).

Referring to FIG. 1A and FIG. 1B, each sail 130 has bottom end 132 andtop end 134. At least a portion of bottom end 132 can be coupled to base120 at attachment points 104. Bottom end 132 can extend along a lengthof base 120. In some embodiments, the width of sail 130 can beapproximately the same as the length of base 120. At least a portion oftop end 134 can be coupled directly or indirectly to frame 110 oranother top tension point.

For example, sails 130 can be coupled together and/or coupled to aconnector (not shown) that couples to frame 110 (e.g., a top portion offrame 110 where legs 112 are coupled). A gap can be disposed between topends 134 of sails 130 and bottom ends 132 of legs 112. This gap canfacilitate rotation of sails 130 and/or connection of sails 130 to frame110. Bottom ends 132 of each sail 130 of turbine 100 can be proximate tobottom ends 116 of legs 112. For example, top end 134 of each of sail130 can be a point, and each pointed end of sails 130 can meet and becoupled (e.g., coupled to allow rotation of sails 130) via a connector.

The connector can directly couple sails 130 to frame 110. In someembodiments, sails 130 can extend along the entire height 104 (e.g.,distance in the direction of central axis of rotation 102) of turbine100. Otherwise, sails 130 can extend only partially along height 104 ofturbine 100 and a connector can have a length that allows sails 130 tobe connected to frame 110.

Sails 130 also include exterior side 136 and opposing interior side 138,both disposed between bottom end 132 and top end 134. At least a portionof exterior side 136 and/or at least a portion of interior side 138 canbe free (e.g., not coupled to other sails, frame 110, and/or the base).By allowing the sides of sails 130 to be at least partially free, deadzones (e.g., areas of zero or negligible fluid flow) can be reduced(e.g., when compared with a sail in which the interior side is coupledto a post). The lack of a mast, which would serve as an obstruction tothe crossflow of air between vanes, is also beneficial because it allowsair to flow between vanes, further improving operating efficiency. Thisdistinguishes described embodiments from most rigid-vane crossflow windturbines, which have additional structures external to the rotatingturbine to channel airflow from a larger swept area into the smallerturbine. This is done to reduce the already high cost of large-scalerigid-vane crossflow designs. Accordingly, described embodiment avoidcost problems or mechanical/operational problems associated withcrossflow vertical-axis wind turbines

Further, the vertical taper of described embodiments increasesstability, especially in high-speed or gusty winds. In contrast, knowncylindrical crossflow designs require an additional structure at the topto hold the vanes in place, basically identical to what is used at thebottom (or opposite end of the turbine). Although the swept area isgreater, the costs and mechanical issues have been demonstrated inpractice to not be worth it.

In some embodiments, connectors can couple proximate corners of sails130. For example, a connector (e.g., a chain linkable to a grommet on asail) can couple each corner of top end 134 of the trapezoidally shapedsail 130. The connectors can meet at a common point and couple to frame110. In some embodiments, other shapes can be utilized as appropriate.Further, sails 130 and/or connectors can couple at a common point priorto coupling to frame 110. For example, connector(s) can couple with endsof triangularly shaped sails 130 at a common point (e.g., a singleconnector can couple all sails 130 and/or multiple connectors can beutilized to couple two or more sails together). The connector can extendfrom the common point to frame 110 (e.g., to couple proximate the secondend of Legs 112). In some embodiments, when sails 130 and the connectorsare coupled, an approximately conical shape (e.g., area of rotation ofsail 130 and/or including the area disposed between connectors) orportion thereof can be formed.

Sail 130 can include batten or cross-member 106 to inhibit cupping ofsail 130 during rotation. Cupping can increase drag of sail 130 andtherefore reduce power generation of a turbine. Sail 130 can include anopening (e.g., sleeve, pocket, recess, etc.) to receive a cross-member.For example, sail 130 can include one or more sleeves disposed betweenits interior side and exterior side. Cross-member(s) 106 can be disposed(e.g., removable and/or fixedly) in the sleeve(s), can be disposed inturbine 100 parallel to the edge of interior end 138 of sail 130 and/orapproximately perpendicular to central axis (e.g., axis of rotation)102.

Referring to FIG. 1C, base 120 includes a plurality of spokes 122.According to the illustrated embodiment, six (6) of spars or spokes 122have similar shapes and/or sizes. By utilizing spokes 122 with similarsizes, installation of turbine 100 is simplified (e.g., when comparedwith base members that have different size pieces) since spokes 122 arenot required to be individually labeled and/or positioned.

Each spoke 122 includes interior end 124 and opposing exterior end 126.As illustrated, interior end 124 of each spoke 122 can be coupled toanother spoke 122 and the exterior end 126 of each spoke 122 can be free(e.g., not coupled to another spoke 122). Spokes 122 can be coupledtogether to form an approximately hexagonally-shaped hub 128 with six(6) free ends (e.g., exterior ends) of spokes 122 radially disposedabout hub 128.

FIG. 1D illustrates an example of mastless turbine 100 where an externalframe is not utilized. Instead, a central connector is utilized tocouple sails 130 to a stationary support, such as support 156. Asmentioned, such embodiments are useful where turbine 100 is implementedin locations that are mobile or the like. According to the illustratedembodiment, turbine sails 130 are placed at tension about their topedges by meeting at a central connecting point 150 that is allowed torotate at its lower end 152, while remaining fixed at its top end 154.This can be effectuated by using a bearing mechanism or the like. Sails130 attach to connecting point lower end 152, which can comprise a hook,loop, latch, or the like, that reversibly couples to sails 130. Duringoperation, connecting point lower end 152 rotates with respect toconnecting point top end 154, which does not rotate. Further connectingtop point 154 attaches to stationary support 156. Support 156 can be anycomponent sufficient to support the weight of connecting point 150 andsupports same when turbine 100 is placed under tension at connectingpoint 150. In some embodiments, support 156 can be a guideline or railon a watercraft, and the like. Further, several of turbines 100 can beplaced along the length of support 156 in daisy chain fashion, providingan array of turbines 100. In this embodiment, platform 142 and stand 140can be components sufficient to place tension on turbine 100 about thebottom edges of sails 130 while remaining fixed to a bottom stationarysupport 158. While not required, in the illustrated embodiment generator108 is housed within stand 140 and rotates therein in response to therotation of sails 130. Further, bottom stationary support 158 can be afixed component in a watercraft or the like. As one can see, such anembodiment is advantageous because it can be implemented in positionsthat are themselves mobile or otherwise inaccessible to turbines thatrequire a fixed central mast.

FIG. 2 illustrates a perspective view of a portion of turbine 100implemented on stand 140 and platform 142. As discussed, stand 140 can,in some embodiments, house generator 108 and have mechanism that allowfor energy transfer to a remote location such as, e.g., energy storage109. From there, energy can be transferred to various end users fordifferent applications. Again, platform 142 can rotate with sails 130and can be solid (as illustrated in FIG. 2 ), or comprise spokes orspires (as illustrated in FIG. 1C), where each spoke extends along thelength of a bottom edge of a corresponding sail 130.

A six (6) sail turbine with a hexagonal hub and spoke base (e.g., asillustrated in FIG. 1C) can generate power and efficiencies overturbines with a different numbers of sails. This is illustrated where,in FIG. 1C, there is a corresponding sail 130 extending from each spoke122. Experimental tests reveal that, when airflow across turbine 100 isconsidered, backwind drag during the upwind portion of an individualsail's cycle is reduced because is falls into the “wind shadow” of thesail ahead of it. At that point, if viewed from the top, the back-windedportion of the cycle is minimal with six (6) sails. For example, four(4) sails may be inflated in a particular direction and two (2) sailsmay be back-winded during at least some operation of the six (6) sailturbine. There is a point during the cycle where the backwind forceequals the forward force and the turbine completely stalls. Accordingly,an optimal function and cost is achieved with six (6) sails. Below thatnumber, the function decreases dramatically. Above that number, the costincreases disproportionately with respect to performance.

Turbine 100 can be collapsible and/or formed from several uncoupleablecomponents to allow ease of transport and/or storage. For example, legs112 and/or spokes 122 of base 120 can be reversibly coupled to oneanother for easy assembly and disassembly. Sails 130 can be flexible andcollapsible (e.g., capable of being rolled or otherwise reduced insize). The turbine can then be installed for operation to generateenergy. Turbine 100 and/or portions thereof can also later be dissembledsimilarly (e.g., to discontinue operations, to move the turbine, toavoid damage due to high fluid flow, etc.).

Turbine 100 can be lightweight when, e.g., an open base (e.g., asopposed to a solid disk shaped base) is utilized. Sails 130 can beformed of lightweight material to facilitate rotation in wind and/orother fluids. In addition, frame 110 can include material that islightweight and provides structural strength to turbine 100. Therefore,transport can be facilitated when utilized lightweight embodiments ofturbine 100.

In some embodiments, turbine 100 or portions thereof (e.g., sails and/orbase) can be elevated from a surface (e.g., the ground). When alightweight turbine embodiment is utilized, if turbine 100 fails (e.g.,collapse of frame 110, uncoupling of components, etc.), less damage canoccur with lightweight components of turbine 100. Additionally oralternatively, using lightweight parts may enable the sails to bequickly dropped and partially furled in advance of extreme weather toreduce or prevent damage.

As mentioned, the energy generated from rotation of sails 130 can bedirectly and/or indirectly transmitted to a machine capable of acceptingthe energy (e.g., torque driven machinery, such as pumps). Therefore,irrigation systems, well pumps, showers, etc., can be directly driven bythe energy from rotation of sails 130. In some embodiments, the energyfrom rotating sails 130 can be converted to a different form of energysuch as electrical energy (e.g., via a generator) and/or pneumaticenergy (e.g., via compression of air). The energy can be stored (e.g.,in batteries and/or compressed air containers), in some embodiments.

Turbine 100 can be part of a turbine array and used in conjunction withan energy storage unit(s) 109. To that end, an energy storage unit 109can be utilized in conjunction with one or more turbines 100 in thearray and used to efficiently distribute energy to local or remotelocations.

Importantly, the energy storage unit 109 can be utilized in conjunctionwith the one or more turbines 100 to produce a constant or near constantenergy output over time and under varying conditions. That is, duringoperation, all or a portion of the energy generated by the one or moreturbines 100 can be distributed to the energy storage unit 109. Duringperiods of low wind speed, and likewise, low turbine power output, theenergy storage unit 109 can be used to increase overall energy output tocompensate for a decrease in turbine energy output. During periods ofhigh wind speed, and likewise, high turbine power output, the energystorage unit 109 can be used to provide no or minimal energy output tomaintain overall energy output at a constant or near constant level.

Referring to FIGS. 1A-1D and FIG. 2 , in some implementations, stand 140can be utilized with turbine 100. Generator 108, which can be housed instand 140, is, of course, utilized as a means to extract power fromturbine 100. While generator 108 and stand 140 are, in one respect,ancillary to turbine 100 itself, instantiation of each is necessary foran integrated system, according to some embodiments. In the illustratedembodiment, generator 108 and stand 140 can be generic where a varietyof generators, alternators, and gearbox setups are possible beneath asingle stand design.

Nevertheless, embodiments are intended to require only minimal cost. Tominimize cost and increase operational efficiency, embodiments involvetransmitting torque from turbine 100 to generator 108 (which mayfunction as an alternator) and isolating the alternator and its internalbearings from undesirable dynamic loads (anything other than rotatingtorque) that might be transmitted from turbine 100. Also, embodimentsprovide solid anchoring of turbine 100 to minimize horizontal andvertical displacement or movement of turbine 100 while allowing rapid,modular deployment of components as well as access for maintenance orreplacement/swap-out of components as necessary, with minimal effort,and with safety at the forefront.

Also, it has been recognized that use of an alternator (not shown, incommunication generator 108) that operate at the same RPM as turbine 100becomes less economical as the size of turbine 100 increases. Therefore,a gearbox can be used in generator 108 to “step-up” the RPM rate so thatthe power of turbine 100 can be matched to the power output andvoltage/current ranges of alternator. For a given turbine 100, a single,“one size fits all” stand would be desirable. The 3-stage design of thestand, the gearbox, and the alternator satisfies this.

FIGS. 3A-3H illustrate various views of an example of stand 140. Stand140 holds an alternator or pump in position beneath turbine 100, toprevent it from rotating. For instance, if turbine 100 is implemented ona watercraft, it would be desirable to house the entire unit in a “hatbox” type of arrangement, to keep salt water and spray out of it as muchas possible. In any event, the design of components beneath turbine 100can be ancillary to turbine 100 itself.

The illustrated implementations enable a gearbox appropriate to almostany alternator, pump or other apparatus to be attached to turbine 100.The upper end of the gearbox fits into a receptacle on the underside ofthe top pate of stand 140. It is pulled into position by attaching thealternator to the gearbox (matching hardware depends on alternatordesign), and jacking it upwards into place by alternately rotating thethree jackscrew rods. During this process, the shaft at the top of thegearbox moves upwards into position through a hole in the center of thetop plate of stand 140. This hole is surrounded by the male end of thelabyrinth seal (just a ½-inch high pipe section of proper diameter).Near the top of the shaft, horizontal cross-hole accommodates a boltwhich goes through the drive plate and shaft. This arrangement holds thegearbox and alternator securely in place, meeting all of therequirements listed above.

Referring to FIGS. 3A-3H, stand 140 can include platform 142 and aplurality of legs 144. Stand 140 can also house generator 108. Platform142 can support a machine that is, for example being directly driven byturbine 100 and/or converting the energy produced into a different formof energy (e.g., generator 108). As seen in FIGS. 3A-3H, generator 108can be coupled to platform 142 of stand 140. Legs 144 of platform 142can be coupled to the ground proximate turbine 100. Stand 140 can atleast partially secure the machine and the connection between themachine and turbine 100 during the stresses of operation (e.g., torqueapplied to stand 140 from the rotation of sails 130).

Access ports can be added to the gearbox so that it can be inspected andlubricated without dropping the entire box down with the jackscrews andremoving the side plate from the gearbox. The exact axis of rotation forthe alternator does not need to be aligned with the turbine 100. Onlythe drive plate at the top of the stand does. Even this can be a littlebit off, up to a couple of inches, which is an indication of therobustness of this design.

The following examples illustrate the various end use applications,functionality, and advantages provided by aspects described herein.

Example 1

In some embodiments, turbine 100 can be utilized in combination with ashelter. For example, turbine 100 can include an external frame, sails,and a base. Sails 130 can be coupled proximate a first end to base 120and coupled (e.g., directly or indirectly) to the external frameproximate the second opposing end. The external frame can include afirst end and a second opposing end. The second opposing end can bedisposed proximate the ground. Sails 130 and base can be disposedproximate the first end of frame 110. The external frame can have aheight (e.g., distance between the first end and the second end) thatprovides a shelter for people, animals, and/or other appropriate peopleor items (e.g., machinery) beneath sails 130. For example, sails 130 canbe disposed at a height (e.g., greater than or equal to approximately 6feet, 8 feet, etc.) above the ground and/or second end of frame 110. Asa result, a cavity can be disposed in frame 110 below sails 130. Thiscavity can be utilized for shelter and/or storage. In some embodiments,a roof can be disposed below sails 130. In some embodiments, sails 130and/or base member can be coupled to a device (e.g., a generator) toutilize, convert, and/or store the power generated by turbine 100. Thedevice can be disposed on stand 140, on the ground, and/or on a roof ofthe shelter. Therefore, the assembly with turbine 100 and shelter canprovide power and/or shelter to people, animals, and/or otherappropriate animals or devices.

Example 2

Referring to FIG. 4 , turbine 100 can be implemented as a watercraftsail turbine 400. For instance, turbine 400 cab be implemented on acatamaran or the like. According to such an embodiment, turbine sails430 absorb wind energy and convert same into rotational torque. Thetorque can either drive a generator, mechanical linkage to a propeller,or pump mechanism. Energy can be stored in the form of batteries, H2(fuel cells), compressed air, etc. Advantageously, a water craft cansteer in any direction (e.g., unlike a traditional sailboat) andmaintain operation of turbine 400. Turbine sails 430 can be raised orlowered at any time. With stored energy the water craft can continue tooperate with sails 430 lowered or without wind. The catamaran can bemanned or remotely/autonomously piloted. Turbine 400 can be scalablefrom very small, i.e., <1 meter, to 10s of meters.

Example 3

Turbine 100 can be used to pump water from a well. Turbine 100 canreplace traditional windmills, which can often include heavy metalobjects suspended in the air, and/or electrical pumps, which can becostly to operate. The described turbine can be quieter than standardpumps.

Example 4

Turbine 100 can be utilized in combination with water purificationsystems. Some types of water purifiers (e.g., reverse osmosis) requireonly that water be pumped through them to purify water. Therefore,turbines can be used to pump water through the water purification systemand provide cleaner water to an end user. In conventional waterpurification systems, power is usually supplied in electrical form, viautility, solar panels, electrical wind turbines, or animal power.However, turbine 100 can be connected directly to pumping mechanisms,eliminating the requirement for electrical subsystems. This setupincreases reliability and improves safety, while reducing cost. Further,such a setup can be built at any appropriate scale.

Example 5

Turbine 100 can be used in an inverted arrangement in a body of water.Sails 130 can be rotated by the flow of water over sails 130 and theenergy generated can be provided to directly or indirectly drive amachine, converted to another form of energy, and/or stored.

Example 6

A wind turbine can be provided as follows. The vertical axis conicalsail turbine is a form of cross flow turbine that is comprised of rigidor flexible (e.g., fabric) sails, supported externally by tensileelements (halyards, etc.) at the top, held open and in shape at thebottom by one or more spar elements.

To enable and facilitate rotation, the suspension arrangement involvesthe use of a swivel bearing above the top of the wind turbine, to whichthe halyard and associated rigging is connected. Alternatively, theswivel can be connected directly to the supporting member, provided thatthe support can be adjusted in order to create the proper tension insail 130 members (especially if these are non-rigid).

Turbine 100 can be used to perform useful work, as the flow of workingfluid (usually air or water) moves generally across and through turbine100 transverse to turbine 100's axis of rotation. In other words,turbine 100 rotates around a vertical axis in response to generallyhorizontal fluid flow.

The power of the working fluid impinging on the device is well-known,and expressed as the cube of the velocity (u) of the fluid multiplied byturbine 100's frontal cross sectional area (A), multiplied by thedensity of the fluid (p or rho), or as the equation:P_impinging=0.5*u{circumflex over ( )}3*A*p

The Power extracted from a given turbine (if that is its intendedpurpose), is considerably less than the impinging power, and can berepresented with the introduction of a coefficient of harvest (Charvest), such that:P_harvest=P_impinging*C_harvest

For fluid-based turbines, C_harvest is limited by the Betz limit, andtypically much lower. Horizontal axis turbines typically operate with aC harvest of 0.25 to 0.40. Vertical axis turbines have lower C harvestvalues because a portion of turbine 100 is always driving into the wind,lowering efficiency, creating drag.

Not all wind or fluid energy harvesting situations are best determinedby considering only the mechanical efficiency of the device. Overalleconomic efficiency, or applied utility, given particular circumstances,can offer compelling reasons for the embodiment of less aerodynamicallyefficient devices. Some of these reasons might include: cost; safetyfactors; size of individual components and relationship toinfrastructure for access and Maintenance; environmental impact;creation of so-called wind-shadows; noise; effects on wildlife (hazardsto flying creatures, etc.); aviation hazards; radar interference, andlimitations imposed by application (e.g., marine use, portability,etc.).

The wind turbine would therefore be one that for a particular purpose isthe best overall fit to a list of requirements and constraints,including but not limited to those listed here.

In Situ measurements of mastless turbine 100, with the originally shownembodiment using a pair of curved sails, have demonstrated C_harvestvalues in the range of 02 to 0.22 in relatively low wind speeds of up to8 meters per second. This is considerably greater than the originallyanticipated C_harvest of 0.15, which is the range of Savonius turbines(from which the original base shape is derived). The reasons for thisapparent increase in C_harvest remain under study, but are believed tobe related to the conical shape of sail 130 members, which add avertical slope component and allow vertical shedding of drag (similar toa motorcycle fairing) that does not occur in a typical Savonius design.

The power from turbine 100 is extracted from a mechanical linkage toturbine 100's base spar (or spar system), in the form of rotationaltorque, where Power is expressed as a function of the Torque multipliedby the rate of rotation.

The rate of rotation of all forms of sails 130 is limited at the outsideedge of turbine 100 by the speed of the wind itself. In other words, thetip speed ratio is at or below approximately 1:1 of that of the windspeed. Application of a load to turbine 100, to extract power, inhibitsthe rate of rotation. Various forms of tuning of power extraction,usually through gating of electrical power, can be employed so thatturbine 100's rotational rate is at its most efficient with respect tothe wind speed. Overly dragging turbine 100 results in wasted energy dueto turbulence, although in many instances this might be tolerable, astuned power extraction systems add cost.

Sail Design and Configuration

According to an embodiment, a minimum number of sails is generallyconsidered to be two sails, which also might be made as a single sailwith a curvature through the middle (with or without gaps for cross flowof working fluid). Non-cross flow variations are less efficient and aretherefore of reduced utility.

The use of curved sails, while aerodynamically desirable, does have itsdownside. The shape of the curve at base 120 is a complex recurveresulting from the oblique

Cone-Shape of Turbine 100

If the curvature is not precisely constructed (which includes allseaming and mounting), turbine sails 130 end up with wrinkles and kinksand are less than ideal, both in performance and aesthetics.Furthermore, as the scale of turbine 100 increases, curved battens mustbe introduced which increase complexity and cost.

Variations of turbine 100 with more than two sails are envisioned. Amongthese variations, changes in the curvature of sails 130, including nocurvature, are included as potential embodiments. To that end, avariation of turbine 100 with six (6) flat sails can be easilyconstructed, but any number of sails might be considered. It has beendetermined that an embodiment with six (6) sails is an attractiveconfiguration, being less costly, easier to construct and transport,etc., than the two (2) sail version.

For a multi-sail version, base 120 (or spar) consists of severalidentical components (straight or curved, but straight is shown), whichcan be attached to create the final spar shape. Sails 130 are attachedto the spar by various means, including beaded welting, looped fabricover the spar, hold-down lines, etc.

As an example, a perfect hexagonal shape is formed from 6 identicalspars, connected to each other at their midpoint. This geometricconfiguration results in 60 and 30 degree angles, with the spars joinedat exactly their midpoints to the end of the succeeding spar. Thesestraight components are easy to store and transport (relative to acurved spar), as they can be bundled and fit into a container or bag.The spar length to overall diameter can be expressed as the tangentfunction of 30 degrees times base diameter (0.5773*D). This isconvenient because construction requires little in the way of precisetooling or measuring of angles—all of the angles are a result of lengthsof components.

Base length of sails 130 is nominally from the outermost end of the sparto the midpoint of the spar, but can be more or less as experimentsreveal the most economical configuration. More sail material increasescosts of materials so must be balanced against energy harvestefficiency. The minimum amount of sail material possible should beemployed in turbine 100's construction to minimize cost.

The flat triangular shape of sails 130 in the multi-sail configurationis easy to fabricate, especially if made as flat sails (having nocurvature in the radial direction). As a triangle, the letters A, B, andC can be used to designate the bottom inner, bottom outer, and topvertices. By simple geometry, the three-dimensional coordinates of thesevertices can be represented by points (x, y, z), where x and y representthe radial plane and z represents the axial plane, and are expressed inwhatever measurements units are desired, (e.g., inches, feet, meters,etc.).

These coordinates can be used as inputs into the 3-dimensional distanceformula to determine the exact lengths of the 3 legs of the sailtriangle (to which there is only a single constructible solution). Oncea pattern for a given sized sail is made, sails can be readily produced,and dimensions are independent of choice of fabric, color, etc. Further,computer-aided or otherwise controlled methods can be implemented todetermine the dimensions of sails 130 and reproduce same in the mostefficient manner.

Adaptations for Use of Mechanical Power

The rotating torque from turbine 100 can be used to directly orindirectly power electrical generators or alternators, with or withoutRPM/torque translation, inline (on axis) or off axis from turbine 100,or at various angles to turbine 100's axis of rotation. The electricitycan be utilized in any way that electricity might be utilized to drivesecondary electrical devices of all forms.

The rotating torque from turbine 100 can be used to directly orindirectly power rotating equipment not utilizing electrical means,including: pumps (water, air, or hydraulic) to drive fluid from onelocation to another, linear equipment (rotational to lineartranslation), crankshafts, and the like.

Further, use of embodiments described herein include uses in dedicatedsystems, such as: (1) Manufacture of Hydrogen Gas by means ofelectrolysis of Water (H₂O); (2) Charging of battery systems orconnection to battery-based of fuel-cell based systems for localizedenergy storage; (3) Manufacture of other chemicals (e.g., methane,ammonia); and (4) Direct or electrically operated pumping systems forwater purification, desalination, or sewage treatment. As an example, a1-meter (base diameter turbine) operating at an NCF of 0.2, can produce50-100 gallons of desalinated potable water per day, enough to meet thesurvival needs of 50-100 people. A 3-meter turbine, easily set up by oneor two persons, will process 9 times as much, enough for over 450people.

Operation of Groundwater Pumps (Water Wells) Whether of Mechanical orElectrical Form

Turbine 100 can also be used in a system to refit to water wellsemploying traditional “farm windmills.” This can be accomplished with amechanical adaptor to the well's existing down-hole apparatus. Theresulting system is less costly and eliminates the climbing hazardsassociated with the older design. The conical turbine does not need tobe directly over the well, as the mechanical power can be transmitted bymeans of shafts, belts, endless rope drives, etc.

Other end-use applications include: Auxiliary power for a boat, Directmechanical operation of pumping apparatus on a boat, Bilge & otherpumps, Water makers, Power for propulsion of a boat or water craft,Direct linkage to propeller or other thrust-creating system, andIndirect by means of electrical systems (batteries, fuel cells, etc.) todrive electrically driven propulsion devices. Further, one or moreturbines might be employed on a vessel for this purpose, with permanentor non-permanent mast structures from which to support turbine 100

Support Structures

As discussed, sails 130 are not supported from the bottom or internallyby a central shaft, but from above and below. Any support structurewithin reason can be used to support turbine 100, provided that it istall enough for sails 130 to be fully deployed and for other practicalmatters pertaining to turbine operation, and has sufficient structuralintegrity to allow turbine 100's sails to be properly tensioned foroperation via the halyard.

Categories of turbine support structures include: A line (standingrigging) from tree to ground or another tree or structure, from whichone or more turbines can be suspended, Geological features (cliffs,between hillsides), Man-made features, Pre-existing, originally forother purposes (building, towers, masts, etc.), specially built orerected for use by sail turbines, A-frames, Open Tripods (gyns), Arches,tall single-mast tower with guys to support tower and turbines, andLines (standing rigging) between any of the aforementioned from whichone or more turbines can be suspended.

Various forms of self-erecting structures can be employed. Embodimentscan be utilized in conjunction with a form of self-erecting tripod and adouble A-frame that are both suitable for rapid deployment of theconical sail turbine (as well as other applications). These structurescan be quickly raised from a basically flat position on the ground tofully erect by means of a single halyard attached to at or near the topof one member and run through a block or compound block set on the othermember.

This structure would be suitable for use on a boat (such as a catamaran)powered by a conical sail system, as it would enable the entire rig tobe lowered to deck level when desired or necessary, such as whentrailering (ground transport), passing under a low-clearance obstacle,reducing windage or visibility (low detectability) when operating underpowered mode.

As a ground-based system, the ability to raise and lower such astructure would be desirable as a one-person installation feature orwhen an approaching storm (such as a tropical cyclone) approaches.

In general, it is the intention of the inventor that these structuresshould not require personnel to climb to the top, and that all actionsshould be possible from the ground via halyards and lanyards. However,it is recognized that there might be special circumstances requiringdirect access to the top of the structure. For this, permanent ortemporary rungs can be added to one or more legs of the structure(provided that the strength is appropriately rated to handle the weightof a climber). Alternatively, secondary means can be used (ladders,lifts, etc.) to access the top of the structure. In all suchcircumstances where climbing by a human is to be considered, safety isof the utmost importance.

Another tripod raising method involves connecting all three legs at thevertex, with opposite legs, which form an A-frame, fixed the ground attheir bases such that they can freely pivot upwards into deployedposition. The third leg is connected to the other two at the vertexbetween them, and a large pin or other through-fastener holds the vertextogether so that the members can be moved into upright position. In thiscase, base 120 of third member can be pushed or pulled (e.g., by a winchtethered to the A-frame bases) which causes the vertex to rise intoposition. Once erected, base 120 of the third member is securelyanchored so that it will not move laterally on the ground.

Lowering the tripod is simply a matter of reversing the deploymentsequence. Base 120 of the third leg is attached to a winch or othermechanism in the direction of the center between the bases of theA-frame legs, in order to control the descent. Base 120 of the third legis pulled away from the winch while the winch is let out to control theprocess and prevent the structure from suddenly collapsing. This processis followed until the vertex is close enough to the ground to besupported by a smaller temporary support (or person) and then loweredthe remaining distance at the center (the forces on base 120 become toostrong as the vertex opening angle approaches 180 degrees).

Another way of raising the tripod is to add sections to each leg fromtheir respective bases. The leg sections would attach by means known tothe art. For example, legs 112 can be constructed of sections of pipe,necked down at the upper ends so that they can be inserted into thepreceding sections, and secured with locking pins.

Safeguards

Safeguards of various forms can be employed to protect turbine 100 andpeople/animals from damage or injury as a result of abnormalcircumstances. Turbine 100's base spar can be encircled with a hoop toreduce the possibility of collision of a person or animal moving intothe spar's rotational zone.

Sensors or trips can be used to determine if an object (typically personor animal) encroaches into turbine 100's safety zone and engage to haltor slow the rotation of turbine 100. Turbine 100 spars can be positionedhigh enough so as to be out of the way of normal interactions withhumans or animals expected to be in the area (e.g., 7-8 feet aboveground).

Various means can be employed to automatically trigger release of thehalyard in the event of high winds or halyard loads in excess of apredetermined value. Such devices can be purely mechanical,electromechanical, automatic, or remotely controlled. As an example, atrip mechanism can be used to simply release the halyard based ontension loading to the halyard itself. As another example, the halyardmight be raised and lowered by a winch mechanism, which might be eitherhand-cranked or driven by electrical or hydraulic means. Also, the winchmight be either manually or autonomously actuated by either on-locationcontrol systems or from a remote control point.

Ice buildup on turbine 100's sails can be anticipated under certainweather conditions. Modest ice buildup on turbine 100's sails will havelittle effect on operation. Moreover, the flexible nature of sails 130will naturally provide some movement (flexion) that will tend to breakice sheets into fragments and cause the ice to shed withoutintervention. Due to the relatively slow rotation of turbine 100,horizontal shedding or slinging of ice over significant distances is nota hazard. Ice shedding will tend to be downwards from sails 130. In theevent that drifting or shedding of ice builds up to base 120 of thespars, the worst consequence is that turbine 100 won't turn until theice or snow obstruction is relieved. Base 120 level of turbine 100 canbe engineered to account for seasonal snow depths to minimize thepotential for snow-related turbine stoppages.

Hailstones are a hazard to many wind turbines, as they can cause pittingof metal blades or create cracks in fiberglass or composite blades. InHorizontal axis turbines, the hail, which is falling vertically, canimpact the upward-moving blade tips at relative velocities in excess of400 mph. In contrast, sail 130 turbines shape and materials render itvirtually immune to the effects of hail. The high vertical angle ofsails 130 is nearly parallel to the path of the falling hailstones,which impact sails 130 at a very high (glancing) angle. Furthermore, theflexibility of sail 130 material itself yields slightly upon impact andrecovers; indeed, the same fabrics used for sails 130 are commonly usedat auto dealerships in dedicated hail protection coverings or awnings.

Turbine with Stationary Sails

FIG. 5A illustrates a front view of an example of turbine 500 withstators (e.g., stationary sails) according to one or more aspects, andFIG. 5B illustrates a top-down view of turbine 500 with statorsillustrated in FIG. 5A. Turbine 500 can be used to generate energy(e.g., mechanical and/or electrical) from air flow. For example, turbine500 can be positioned in an area and subject to air flow (e.g., highwind speed and low wind speed).

Turbine 500 includes frame 510, rotating platform or base 520, a firstplurality of sails (referred to herein as first sails 530) (e.g.,vanes), and a second plurality of sails (referred to herein as secondsails 560). In the implementations shown in FIG. 5A, frame 510 is anexternal frame (e.g., external to first sails 530) and operates tosupport and place tension on first sails 530 in an upward direction inthe orientation shown in FIG. 5A. By placing first sails 530 undersufficient tension using frame 510, first sails 530 may efficientlyrotate in response to wind without a central mast. In some otherimplementations, tension may be placed on first sails 530 by attachingeach sail to a central point of tension that is not an external frame,such as a central hook or the like, where the hook is free to rotate atone end while being held stationary at another end. This may beeffectuated through the use of bearings or the like, and is advantageouswhere turbine 500 is installed in compact locations where an externalframe would not fit.

Frame 510 can include any appropriate material to provide theappropriate strength to turbine 500. For example, frame 510 may beformed from wood, plastic, metal or a metal alloy, or the like, asnon-limiting examples. Frame 510 may at least partially support firstsails 530, base 520, second sails 560, or any combination thereof, andcan be self-erecting and/or manually erected (e.g., by a person).

In some implementations, frame 510 includes at least three legs 512, asshown in FIG. 5A. In other implementations, frame 510 includes fewerthan three or more than three legs. Legs 512 each have top end 514 andopposing bottom end 516, and legs 512 can be positioned such that topends 514 are disposed proximate each other while bottom ends 516 arespaced from one another about the circumference of the circle swept outby first sails 530 and/or base 520 during rotation of first sails 530.Therefore, the ends of legs 512 are uncoupled at or about a bottomportion of frame 510, and coupled (e.g., directly or indirectly) at orabout a top end of frame 510. For example, frame 510 can have three legs512 in a shape arranged as a triangular pyramid, where top end 514 ofeach leg 512 converges near an axis of rotation of first sails 530 whilebottom ends 516 of each leg 512 are spaced from one another about thecircumference of the circle swept out by first sails 530 and/or base 520during rotation of first sails 530. In some implementations in whichlegs 512 include three legs, legs 512 may be disposed such that each legextends to a position that is radially separated from positions of theother two legs by approximately 120 degrees, thereby balancing thesupport provided by legs 512 to turbine 500.

In some implementations, the ratio of a height of frame 510 to a widthof frame 510 can be between approximately from 1-to-1 to 2-to-1, whilein a preferred implementation the ratio of the height of frame 510 tothe width of frame 510 is approximately 1.3 to approximately 1. However,it should be appreciated that frame 510 can be any height, even muchgreater than that of turbine 500 itself. For example, the height offrame 510 may be increased to increase the ground clearance of turbine500 for any number of reasons. Further, the size of frame 510 can beselected to allow first sails 530 to rotate within frame 510 withoutcontacting legs 512. The ratio of the height of frame 510 to the widthof frame 510 can be approximately the same as the ratio of the height offirst sail 530 to the width of first sail 530, and the overall height offrame 510 can be larger than the overall height of first sail 530.

Base 520 (e.g., a platform) can include any appropriate material, suchas metal, fiber reinforced plastics, and/or wood. Preferably, to reduceweight of turbine 500, base 520 can form an open frame (e.g., at leastapproximately 50% of the footprint of base 520 is open and/or componentsof base 520 comprise an area of less than approximately 50% of thefootprint of base 520). Base 520 may be unitary or may be assembled frommultiple pieces or components, and may have any shape, such as acircular shape, an ellipsoid shape, a polygonal shape, a more complexshape, or another shape, and the shape of base 520 may depend on thenumber of sails included in first sails 530. Base 520 may be coupled toor in communication with a generator 508 that is configured to generateenergy based on rotation of base 520 and/or first sails 530, asdescribed above with reference to generator 108 of FIGS. 1A-D and FIG. 2. In some implementations, generator 508 may be centrally aligned withaxis of rotation 502. Additionally or alternatively, generator 508 maybe coupled to or in communication with one or more energy storage units509, such as one or more batteries, power cells, or the like, that areconfigured to store energy generated by generator 508.

First sails 530 can rotate in the presence of a fluid flow (e.g., wind)about a central axis of rotation 502 to generate energy. Each of firstsails 530 may have a shape that is wider at bottom end 532 than at topend 534. For example, first sails 530 may be approximatelytriangularly-shaped or approximately trapezoidally-shaped. When firstsails 530 are positioned in turbine 500, an exterior side 536 of firstsails 530 can form an approximately conical shape and/or at least aportion of a conical shape. In some implementations, the ratio of aheight of one of first sails 530 to a width of one of first sails 530can be approximately 2-to-1. In a particular implementation, the ratioof the height of first sails 530 to the width of first sails 530 can beapproximately 1.3 to approximately 1.

Turbine 500 can include an even or odd number of first sails 530, whereeach of the sails may be formed of any appropriate material. In someimplementations, first sails 530 can include a material that allowsfirst sails 530 to collapse, be rolled, and/or otherwise reduced in sizefor storage, transport, and/or other appropriate reasons (e.g., windsexceeding a predetermined maximum velocity). For example, first sails530 may include one or more types of fabrics, plastic, one or moresynthetic fibers, other materials, or a combination thereof, asnon-limiting examples.

As shown in FIG. 5A, each of first sails 530 has bottom end 532 and topend 534. At least a portion of bottom end 532 can be coupled to base 520at attachment points 504. Bottom end 532 (e.g., a particular end offirst sails 530) can extend along a length of base 520. In someimplementations, widths of first sails 530 can be approximately the sameas the length of base 520. At least a portion of top end 534 (e.g., anopposite particular end of first sails 530) can be coupled directly orindirectly to frame 510 or another top tension point. For example, firstsails 530 can be coupled together and/or coupled to a connector (notshown) that couples to frame 510 (e.g., a top portion of frame 510 wherelegs 512 are coupled). A gap can be disposed between top ends 534 offirst sails 530 and top ends 514 of legs 512. This gap can facilitaterotation of first sails 530 and/or connection of first sails 530 toframe 510. For example, top end 534 of each of first sails 530 can be apoint, and each pointed end of first sails 530 can meet and be coupled(e.g., coupled to allow rotation of first sails 530) via a connector.The connector can directly couple first sails 530 to frame 510. Bottomends 532 of first sails 530 can be proximate to bottom ends 516 of legs512. In some implementations, first sails 530 can extend along an entireheight 503 (e.g., distance in the direction of central axis of rotation502) of turbine 500. In some other implementations, first sails 530extend only partially along height 503 of turbine 500, as shown in FIG.5A, and a connector can have a length that allows first sails 530 to beconnected to frame 510.

In some implementations, connectors can couple proximate corners offirst sails 530. For example, a connector (e.g., a chain linkable to agrommet on a sail) can couple each corner of top end 534 of thetrapezoidally shaped first sails 530. The connectors can meet at acommon point and couple to frame 510. Alternatively, other shapes can beutilized for sails as appropriate. Further, first sails 530 and/orconnectors can couple at a common point prior to coupling to frame 510.For example, connector(s) can couple with ends of triangularly shapedfirst sails 530 at a common point (e.g., a single connector can coupleall first sails 530 and/or multiple connectors can be utilized to coupletwo or more sails together). The connector can extend from the commonpoint to frame 510 (e.g., to couple proximate to top end 514 of legs512). In some implementations, when first sails 530 and the connectorsare coupled, an approximately conical shape (e.g., as formed by an areaof rotation of first sails 530 and/or including the area disposedbetween connectors) or portion thereof can be formed.

First sails 530 also include exterior side 536 and opposing interiorside 538, both disposed between bottom end 532 and top end 534. At leasta portion of exterior side 536 and/or at least a portion of interiorside 538 can be free (e.g., not coupled to other sails, frame 510,and/or base 520). By allowing the sides of first sails 530 to be atleast partially free, dead zones (e.g., areas of zero or negligiblefluid flow) can be reduced (e.g., when compared with a sail in which theinterior side is coupled to a post). The lack of a mast, which wouldserve as an obstruction to the crossflow of air between sails, is alsobeneficial because it allows air to flow between sails, furtherimproving operating efficiency and avoiding cost problems ormechanical/operational problems associated with crossflow vertical-axiswind turbines, as described above with reference to FIGS. 1A-B.

In some implementations, first sails 530 can include batten orcross-member (not shown) to inhibit cupping of first sails 530 duringrotation. Cupping can increase drag of first sails 530 and thereforereduce power generation of a turbine. In some such implementations,first sails 530 can include an opening (e.g., sleeve, pocket, recess,etc.) to receive a cross-member. For example, first sails 530 mayinclude one or more sleeves disposed between interior side 538 andexterior side 536. Cross-member(s) can be disposed (e.g., removableand/or fixedly) in the sleeve(s), can be disposed in turbine 500parallel to the edge of interior side 538 of first sails 530 and/orapproximately perpendicular to axis of rotation 502 (e.g., the centralaxis of turbine 500).

Second sails 560 are configured to remain stationary in the presence ofa fluid flow (e.g., wind) while first sails 530 rotate about centralaxis of rotation 502. Each of second sails 560 may have a shape that iswider at bottom end 568 than at top end 566. For example, second sails560 may be approximately triangularly-shaped or approximatelytrapezoidally-shaped. When second sails 560 are positioned in turbine500, an exterior side of second sails 560 can form an approximatelyconical shape and/or at least a portion of a conical shape. In someimplementations, the ratio of a height of one of second sails 560 to awidth of one of second sails 560 can be approximately 2-to-1. In aparticular implementation, the ratio of the height of second sails 560to the width of second sails 560 can be approximately 1.3 toapproximately 1.

Second sails 560 may include the same types of materials or differenttypes of materials than first sails 530. In some implementations, secondsails 560 can include a material that allows second sails 560 tocollapse, be rolled, and/or otherwise reduced in size for storage,transport, and/or other appropriate reasons (e.g., winds exceeding apredetermined maximum velocity). For example, second sails 560 mayinclude one or more types of fabrics, plastic, one or more syntheticfibers, other materials, or a combination thereof, as non-limitingexamples. Second sails 560 may have the same shape or different shapethan first sails 530, and may have the same size or different size thanfirst sails 530. In a particular implementation, a cross-sectional areaof each of second sails 560 is greater than a cross-sectional area ofeach of first sails 530. For example, both first sails 530 and secondsails 560 may have triangular shapes, but a width of second sails 560may be greater than a width of first sails 530. Using second sails 560with a greater cross-sectional area than first sails 530 may increasethe swept area more as compared to other implementations. Alternatively,the cross-sectional areas of second sails 560 may be the same or lessthan the cross-sectional areas of first sails 530.

As shown in FIG. 5A, each of second sails 560 has a bottom end 568 and atop end 566. At least a portion of bottom end 568 can be coupled to oneor more stationary surfaces at attachment points 564 along bottom end568. Bottom end 568 (e.g., a second end of second sails 560) can becoupled to one or more stationary surfaces, such as the ground, one ormore non-movable bases, one or more frames, or the like, usingconnectors 569. For example, connectors 569 may include rope, chains,twine, cords, posts, clips, nails, screws, pegs, or any other type ofcomponent capable of coupling bottom end 568 of second sails 560 to astationary surface. At least a portion of top end 566 (e.g., a first endof second sails 560) can be coupled directly or indirectly to frame 510or another top point. For example, second sails 560 can be coupledtogether and/or coupled to a connector (not shown) that couples to frame510 (e.g., a top portion of frame 510 where legs 512 are coupled). Afirst gap can be disposed between top ends 566 of second sails 560 andtop ends 514 of legs 512, and a second gap can be disposed between topends 566 of second sails 560 and top ends 534 of first sails 530. Thesegaps can facilitate rotation of first sails 530 while enabling secondsails 560 to remain stationary. For example, top end 534 of each offirst sails 530 can be a point, and each pointed end of first sails 530can meet and be coupled (e.g., coupled to allow rotation of first sails530) via a first portion of a connector, and top end 566 of each ofsecond sails 560 can be a point, and each pointed end of second sails560 can meet and be coupled (e.g., coupled to prevent rotation of secondsails 560) via a second portion of the connector. For example, the firstportion of the connector may be free to rotate about the axis ofrotation 502 and the second portion of the connector may remainstationary, as further described below with reference to FIG. 5C. Theconnector can directly couple first sails 530 and the second sails 560to frame 510. Bottom ends 568 of second sails 560 can be proximate tobottom ends 516 of legs 512. In some implementations, second sails 560can extend along the entire height 503 of turbine 500. In some otherimplementations, second sails 560 extend only partially along height 503of turbine 500, although farther along than first sails 530, as shown inFIG. 5A, and a connector can have a length that allows first sails 530and second sails 560 to be connected to frame 510.

Second sails 560 also include exterior side 562 and opposing interiorside 563, both disposed between bottom end 568 and top end 566. At leasta portion of exterior side 562 and/or at least a portion of interiorside 563 can be free (e.g., not coupled to other sails, frame 510,and/or a stationary surface). By allowing the sides of second sails 560to be at least partially free, dead zones (e.g., areas of zero ornegligible fluid flow) can be reduced (e.g., when compared with a sailin which the interior side is coupled to a post). In someimplementations, second sails 560 may include a member, such as a spar,a boom, or the like, to increase rigidity of the sail and to provideadditional support. In other implementations, no additional members areincluded to reduce costs of turbine 500.

Turbine 500 can include an even or odd number of second sails 560, andsecond sails 560 may be disposed at particular positions outside of asweeping range of first sails 530 based on the number of second sails560. In the particular implementation shown in the top-down view of FIG.5B, turbine 500 includes four second sails 560 positioned proximate toand outside of six first sails 530. To illustrate, first sails 530 canbe positioned to form an approximately hexagonally-shaped hub with sixfree ends (e.g., exterior sides 536) of first sails 530 radiallydisposed about a center of turbine 500 through which axis of rotation502 extends. In some such implementations, base 520 may include multiplespokes that correspond to, and extend the length of, first sails 530such that the spokes are disposed in the hexagonal configuration shownin FIG. 5B. During rotation of first sails 530, first sails traverse arotational path between an inner turbine diameter 580 and an outerturbine diameter 582, where inner turbine diameter 580 is defined as thesweeping (e.g., rotating) path of interior side 538 of first sails 530,and/or an interior portion of a corresponding spoke, and outer turbinediameter 582 is defined as the seeping (e.g., rotating) path of exteriorside 536 of first sails 530, and/or an exterior portion of acorresponding spoke.

In such implementations, each of the four second sails 560 may bedisposed outside of the sweeping range (e.g., outer turbine diameter582) of first sails 530 and at a respective position that is radiallyseparated by approximately 90 degrees from positions of adjacent secondsails 560. To further illustrate with reference to the orientation shownin FIG. 5B, a first one of second sails 560 (e.g., sail 560 a) may bedisposed substantially above first sails 530, a second one of secondsails 560 (e.g., sail 560 b) may be disposed substantially to the rightof first sails 530 and approximately 90 degrees radially from sail 560a, a third one of second sails 560 (e.g., sail 560 c) may be disposedsubstantially below first sails 530 and approximately 90 degreesradially separated from sail 560 b, and a fourth one of second sails 560(e.g., sail 560 d) may be disposed substantially to the left of firstsails 530 and approximately 90 degrees radially separated from each ofsail 560 c and sail 560 a. Second sails 560 may be positioned such thatan inner duct diameter 584 is formed by a circle connecting interiorsides 563 of second sails 560 and an outer duct diameter 586 is formedby a circle connecting exterior sides 562 of second sails 560. Bypositioning first sails 530 and second sails 560 such that inner ductdiameter 584 is entirely outside of outer turbine diameter 582, secondsails 560 may be located beyond the sweeping range of first sails 530during rotation under the influence of wind. In some suchimplementations, a relationship between outer turbine diameter 582 andinner duct diameter 584 may be approximately 1 to 1.1, and arelationship between outer turbine diameter 582 and outer duct diameter586 may be approximately 1 to 2.0. In implementations in which foursecond sails 560 are included in turbine 500, the positioning of secondsails 560 with respect to a direction of the wind may not significantlychange the effectiveness of turbine 500 due to the symmetric design andthe ability of at least one of second sails 560 to redirect wind flow indesired directions, as further described below.

In some such implementations, each of second sails 560 is disposed at anoblique angle from a radius of turbine 500 instead of being aligned witha radius. To illustrate, second sail 560 c may be disposed such that afirst axis 570 that extends from exterior side 562 of second sail 560 cthrough interior side 563 of second sail 560 c is oblique (e.g., isneither parallel nor perpendicular) to a second axis 572 that extendsfrom the center of turbine 500 (e.g., a center of first sails 530)through interior side 563 of second sail 560 c. In a particularimplementation, second sail 560 c may be disposed such that an acuteangle α formed by an intersection first axis 570 and second axis 572 isbetween approximately 30 degrees and 45 degrees, such as 30 degrees in apreferred implementation. Each of the other second sails 560 may besimilarly disposed and configured. The positioning and angles of secondsails 560 are selected to optimize the improvement to the energyproduction of turbine 500. For example, in other implementations, fewerthan four or more than four second sails 560 may be included in turbine500, and accordingly the radial separation between second sails 560 maybe increased (if the number of sails is decreased) or decreased (if thenumber of sails is increased), and the angle α may be different fordifferent numbers of second sails 560. Additionally, including adifferent number of second sails 560 in turbine 500 may necessitatedifferent positioning of second sails 560 based on direction of the windduring operation. For example, turbine designs including other numbersof sails may not be symmetric in the way the four-sail design is, suchthat one or more of second sails 560 needs to be positioned facing into(or away from or not along the direction of) the wind. Accordingly,other designs may require additional setup and configuration by anoperator. In some such implementations, second sails 560 may be coupledto a second base that is adjustable to reposition the locations ofsecond sails 560, such as by rotating the second base, prior tooperation of turbine 500 (e.g., second sails 560 may be rotated todesired positions and then locked or affixed in place so that secondsails 560 remain stationary during rotation of first sails 530 underinfluence of the wind).

Second sails 560 may be configured to redirect wind to increase theefficiency and power generation of turbine 500 based on rotation offirst sails 530. In the example illustrated in FIG. 5B, the wind may beflowing in a downward direction that causes first sails 530 to rotate ina clockwise direction. Second sail 560 a may block portions of the windthat would otherwise apply force against the rotation of first sail 530a and redirect those portions to apply force in the direction ofrotation of first sail 530 b, thereby reducing “counter drag” (e.g., acountering force) on first sail 530 a and increasing “drive pressure”(e.g., force tangential to the direction of rotation) on first sail 530b. Second sail 560 b may capture portions of the wind that wouldotherwise miss first sails 530 and redirect those portions to applyforce in the direction of rotation of first sail 530 c, therebyincreasing drive pression on first sail 530 c. Second sail 560 d mayredirect portions of the wind that would otherwise apply force againstthe rotation of first sail 530 f and redirect those portions away fromturbine 500, thereby reducing counter drag on first sail 530 f. Due tothe nature of the design shown in FIG. 5B, such redirection is performedby second sails 560 regardless of the direction of the wind (e.g., withdifferent ones of second sails 560 redirecting portions of the wind inthe desired directions), such that drive pressure is increased ondownstream first sails 530 (e.g., sails that are rotating with or awayfrom the direction of the wind) and counter drag is reduced on upstreamfirst sails 530 (e.g., sails that are rotating in an opposite directionas the wind). As such, the preferred implementation of including foursecond sails 560 in turbine 500 as described above may represent adesired tradeoff between cost of second sails 560 and improved energygeneration of turbine 500. As a particular example, the above-describedimplementation may represent an increased swept area of 1.93 to 1compared to a turbine without stationary sails, for an approximately 1to 1 or less increase in cost. Increasing the swept area increases thepower generated by turbine 500, according to Equation 1 below, in whichP is power, p is air density, A is rotor swept area, V is wind speed,and E is the efficiency.

$\begin{matrix}{{Wind}{Power}} &  \\{P = {\frac{1}{2}\rho*A*V^{3}*E}} & {{Equation}1}\end{matrix}$

In a particular aspect, a mastless vertical axis wind turbine (e.g.,500) is disclosed. The mastless vertical axis wind turbine includes afirst plurality of sails (e.g., 530) configured to, during operation ofthe mastless vertical axis wind turbine, rotate about a vertical axis(e.g., 502) under the influence of wind. The mastless vertical axis windturbine also includes a platform (e.g., 520) coupled to the firstplurality of sails and configured to, during operation of the mastlessvertical axis wind turbine, be in tension with the first plurality ofsails at one or more points (e.g., 504) about a particular end (e.g.,532) of the first plurality of sails. The mastless vertical axis windturbine further includes a second plurality of sails (e.g., 560) havingrespective first ends (e.g., 566) that are coupled together and secondends (e.g., 568) that are each coupled to one or more stationarysurfaces. The second plurality of sails are configured to remainstationary as the first plurality of sails rotate under the influence ofthe wind.

FIG. 5C illustrates a front view of another example of turbine 500 withstators according to one or more aspects. In the implementationillustrated in FIG. 5C, an external frame is not utilized. Instead, acentral connector is utilized to couple first sails 530 and second sails560 to a stationary support, such as stationary support 556. Asmentioned, such implementations are useful where turbine 500 isimplemented in locations that are mobile or the like. According to theillustrated implementation, first sails 530 are placed at tension abouttheir top ends 534 by meeting at a central connecting point 550 that isallowed to rotate at its lower end 552, while remaining fixed at its topend 554. This can be effectuated by using a bearing mechanism or thelike. First sails 530 attach to lower end 552, which may include a hook,loop, latch, or the like, that reversibly couples to first sails 530.Second sails 560 attach to top end 554 that reversibly couples to secondsails 560 and that remains stationary (e.g., does not rotate) duringrotation of lower end 552. During operation, lower end 552 of connectingpoint 550 rotates with respect to top end 554, which does not rotate.Further top end 554 attaches to stationary support 556. Stationarysupport 556 can be any component sufficient to support the weight ofconnecting point 550, first sails 530, and second sails 560, andsupports same when turbine 500 is placed under tension at connectingpoint 550. In some implementations, stationary support 556 can be aguideline or rail on a watercraft, or the like. Further, several ofturbines 500 can be placed along the length of stationary support 556 indaisy chain fashion, providing an array of turbines 500. In someimplementations, platform 542 and stand 540 can be components sufficientto place tension on turbine 500 about bottom ends 532 of first sails 530while remaining fixed to a bottom stationary support 558. In theimplementation shown in FIG. 5C, generator 508 is housed within stand540 and rotates therein in response to the rotation of first sails 530.Further, bottom stationary support 558 can be a fixed component in awatercraft or the like. As can be seen, such an implementation isadvantageous because it can be implemented in positions that arethemselves mobile or otherwise inaccessible to turbines that require afixed central mast.

In a particular aspect, a mastless vertical axis wind turbine (e.g.,500) is disclosed. The mastless vertical axis wind turbine includes afirst plurality of sails (e.g., 530) configured to, during operation ofthe mastless vertical axis wind turbine, rotate about a vertical axis(e.g., 502) under the influence of wind. The mastless vertical axis windturbine also includes a platform (e.g., 540) configured to couple thefirst plurality of sails to a first stationary support (e.g., 558). Theplatform is configured to, during operation of the mastless verticalaxis wind turbine, be in tension with the first plurality of sails atone or more points (e.g., 504) about a first end (e.g., 532) of thefirst plurality of sails and to rotate with the first plurality of sailsunder the influence of the wind. The first stationary support isconfigured to remain stationary as the first plurality of sails rotateunder the influence of the wind. The mastless vertical axis wind turbineincludes a second plurality of sails (e.g., 560) having respective firstends (e.g., 566) that are coupled together and second ends (e.g., 568)that are each coupled to one or more stationary surfaces. The secondplurality of sails are configured to remain stationary while the firstplurality of sails rotate under the influence of the wind. The mastlessvertical axis wind turbine further includes a central connector (e.g.,550) configured to couple the first plurality of sails and the secondplurality of sails to a second stationary support (e.g., 556). Thecentral connector is configured to, during operation of the mastlessvertical axis wind turbine, be in tension with the first plurality ofsails about the vertical axis and a second end of the first plurality ofsails.

As described above with reference to FIGS. 5A-C, turbine 500 providesbenefits compared to other horizontal access turbines or vertical axisturbines. To illustrate, including second sails 560 in turbine 500improves the swept area corresponding to turbine 500 for less than 1 to1 increase in cost. For example, including four second sails 560 mayincrease swept area by approximately 20-50% for a cost increase of onlyapproximately 10%. Additionally, second sails 560 reduce parasiticlosses (e.g., counter drag) on some of first sails 530 while alsoredirecting some of the wind to impinge more directly on some of firstsails 530, thereby increasing drive pressure on some of first sails 530.This results in significant improvements to the efficiency of turbine500 and increased power generation during operation of turbine 500.These benefits are achieved through the addition of low cost parts thatdo not significantly increase the overall cost or the complexity ofsetup or take down of turbine 500, making turbine 500 suitable for useat multiple different locations or as part of a low cost energygeneration system. Turbine 500 achieves these benefits over othervertical axis turbines without the cost and drawbacks associated withhorizontal turbines.

Referring to FIG. 6 , a flow diagram of a method for generating energyusing a mastless vertical axis wind turbine according to one or moreaspects is shown as a method 600. In some implementations, method 600may be performed using one or more of the components of turbine 500 ofFIGS. 5A-C.

At 602, method 600 includes configuring a first plurality of sails thatduring operation of the mastless vertical axis wind turbine rotate abouta vertical axis under the influence of wind. For example, the firstplurality of sails may include or correspond to first sails 530 of FIG.5A.

At 604, method 600 includes supporting the first plurality of sailsutilizing a platform that during operation of the mastless vertical axiswind turbine is connected to and in tension with the first plurality ofsails at one or more points about a particular end of first theplurality of the sails. For example, the platform may include orcorrespond to base 520 of FIG. 5A.

At 606, method 600 includes configuring a second plurality of sails thatduring operation of the mastless vertical axis wind turbine remainstationary as the first plurality of sails rotate under the influence ofthe wind. For example, the second plurality of sails may include orcorrespond to second sails 560 of FIG. 5A. The second plurality of sailshave respective first ends that are coupled together and second endsthat are each coupled to one or more stationary surfaces. For example,the first ends may include or correspond to top ends 566 of FIG. 5A andthe second ends may include or correspond to bottom ends 568 of FIG. 5A.

In some implementations, the second plurality of sails includes foursails that are disposed such that each sail of the second plurality ofsails is disposed at a respective position that is radially separated byapproximately 90 degrees from positions of adjacent sails of the secondplurality of sails. For example, second sails 560 may include four sailsthat are disposed and positioned as shown in FIG. 5B. Additionally oralternatively, configuring the second plurality of sails may includedisposing each of the second plurality of sails such that a first axisthat extends from a first side of the second end of the sail through asecond side of the second end is oblique to a second axis that extendsfrom the center of the first plurality of sails through the second sideof the second end. For example, the first axis may include or correspondto first axis 570 of FIG. 5B and the second axis may include orcorrespond to second axis 572 of FIG. 5B. Additionally or alternatively,the mastless vertical axis wind turbine may further include a generator,in communication with the platform, that generates energy in response torotation of the platform. For example, the generator may include orcorrespond to generator 508 of FIG. 5A.

In some implementations, method 600 further includes supporting thefirst plurality of sails and the second plurality of sails utilizing anexternal frame that during operation of the mastless vertical axis windturbine is coupled to and in tension with the first plurality of sailsat one or more points about an opposite particular end of the firstplurality of the sails. The external frame includes a coupling mechanismthat during operation of the mastless vertical axis wind turbineconnects the external frame to the first plurality of sails and thesecond plurality of sails such that the first plurality of sails rotateabout the vertical axis while the second plurality of sails and theexternal frame remain stationary. For example, the external frame mayinclude or correspond to legs 512 of FIG. 5A.

Referring to FIG. 7 , a flow diagram of a method for generating energyusing a mastless vertical axis wind turbine according to one or moreaspects is shown as a method 700. In some implementations, method 700may be performed using one or more of the components of turbine 500 ofFIGS. 5A-C.

At 702, method 700 includes engaging the mastless vertical axis windturbine with a first stationary support and a second stationary support.For example, the first stationary support may include or correspond tobottom stationary support 558 of FIG. 5C and the second stationarysupport may include or correspond to stationary support 556 of FIG. 5C.The mastless vertical axis wind turbine may include a first plurality ofsails that rotate about a vertical axis under the influence of wind. Forexample, the first plurality of sails may include or correspond to firstsails 530 of FIG. 5C. The mastless vertical axis wind turbine mayinclude a platform configured to couple the first plurality of sails tothe first stationary support. The platform is configured to, duringoperation of the mastless vertical axis wind turbine, be in tension withthe first plurality of sails at one or more points about a first end ofthe first plurality of sails and to rotate with the first plurality ofsails under the influence of the wind while the first stationary supportremains stationary. For example, the platform may include or correspondto platform 542 of FIG. 5C. The mastless vertical axis wind turbine mayinclude a central connector configured to couple the first plurality ofsails to the second stationary support. The central connector isconfigured to, during operation of the mastless vertical axis windturbine, be in tension with the first plurality of sails about thevertical axis and a second end of the first plurality of sails. Forexample, the central connector may include or correspond to connectingpoint 550 of FIG. 5C.

At 704, the method 700 includes engaging a second plurality of sails tothe central connector of the mastless vertical axis wind turbine. Thesecond plurality of sails have respective first ends that are coupledtogether and second ends that are each coupled to one or more stationarysurfaces. The second plurality of sails are configured to, duringoperation of the mastless vertical axis wind turbine, remain stationarywhile the first plurality of sails rotate under the influence of thewind. For example, the second plurality of sails may include orcorrespond to second sails 560 of FIG. 5C.

In some implementations, the second plurality of sails includes foursails that are disposed such that each sail of the second plurality ofsails is disposed at a respective position that is radially separated byapproximately 90 degrees from positions of adjacent sails of the secondplurality of sails. For example, second sails 560 may include four sailsthat may be disposed and positioned as shown in FIG. 5B. Additionally oralternatively, each of the second plurality of sails may be disposedsuch that a first axis that extends from a first side of the second endof the sail through a second side of the second end is oblique to asecond axis that extends from the center of the first plurality of sailsthrough the second side of the second end. For example, the first axismay include or correspond to first axis 570 of FIG. 5B and the secondaxis may include or correspond to second axis 572 of FIG. 5B.

It is noted that other types of devices and functionality may beprovided according to aspects of the present disclosure and discussionof specific devices and functionality herein have been provided forpurposes of illustration, rather than by way of limitation. It is notedthat the operations of method 600 of FIG. 6 and method 700 of FIG. 7 maybe performed in any order, or one or more operations may be added oromitted. Additionally, one or more operations of one method may beincluded in another method, such as one or more of the operations ofmethod 600 of FIG. 6 being included in method 700 of FIG. 7 , or viceversa. It is also noted that method 600 of FIG. 6 and method 700 of FIG.7 may also include other functionality or operations consistent with thedescription of the operations of turbine 100 of FIGS. 1A-E, stand 140 ofFIG. 2 , stand 140 of FIGS. 3A-H, watercraft sail turbine 400 of FIG. 4, or turbine 500 of FIG. 5 .

Various modifications to the implementations described in thisdisclosure may be readily apparent to those skilled in the art, and thegeneric principles defined herein may be applied to some otherimplementations without departing from the scope of this disclosure.Thus, the claims are not intended to be limited to the implementationsshown herein, but are to be accorded the widest scope consistent withthis disclosure, the principles and the novel features disclosed herein.

Although the aspects of the present disclosure and their advantages havebeen described in detail, it should be understood that various changes,substitutions and alterations can be made herein without departing fromthe scope of the disclosure as defined by the appended claims. Moreover,the scope of the present application is not intended to be limited tothe particular implementations of the process, machine, manufacture,composition of matter, means, methods and processes described in thespecification. As one of ordinary skill in the art will readilyappreciate from the present disclosure, processes, machines,manufacture, compositions of matter, means, methods, or operations,presently existing or later to be developed that perform substantiallythe same function or achieve substantially the same result as thecorresponding aspects described herein may be utilized according to thepresent disclosure. Accordingly, the appended claims are intended toinclude within their scope such processes, machines, manufacture,compositions of matter, means, methods, or operations.

The invention claimed is:
 1. A mastless vertical axis wind turbine, themastless vertical axis wind turbine comprising: a first plurality ofsails configured to, during operation of the mastless vertical axis windturbine, rotate about a vertical axis under the influence of wind; aplatform coupled to the first plurality of sails and configured to,during operation of the mastless vertical axis wind turbine, be intension with the first plurality of sails at one or more points about aparticular end of the first plurality of sails; and a second pluralityof sails having respective first ends that are coupled together andsecond ends that are each coupled to one or more stationary surfaces,the second plurality of sails configured to remain stationary as thefirst plurality of sails rotate under the influence of the wind.
 2. Themastless vertical axis wind turbine of claim 1, where: the secondplurality of sails includes four sails; and each sail of the secondplurality of sails is disposed at a respective position that is radiallyseparated by approximately 90 degrees from positions of adjacent sailsof the second plurality of sails.
 3. The mastless vertical axis windturbine of claim 1, where a cross-sectional area of each of the secondplurality of sails is greater than a cross-sectional area of each of thefirst plurality of sails.
 4. The mastless vertical axis wind turbine ofclaim 1, where, for each sail of the second plurality of sails, the sailis disposed such that a first axis that extends from a first side of thesecond end of the sail through a second side of the second end isoblique to a second axis that extends from the center of the firstplurality of sails through the second side of the second end.
 5. Themastless vertical axis wind turbine of claim 4, where: the secondplurality of sails includes four sails; and for each sail of the secondplurality of sails, an acute angle formed by an intersection of thefirst axis and the second axis is approximately 30 degrees.
 6. Themastless vertical axis wind turbine of claim 1, further comprising: anexternal frame coupled to the first plurality of sails and the secondplurality of sails, the external frame configured to, during operationof the mastless vertical axis wind turbine, be in tension with the firstplurality of sails at one or more points about an opposite particularend of the first plurality of sails, where the external frame comprises:a coupling mechanism configured to, during operation of the mastlessvertical axis wind turbine, connect the external frame to the firstplurality of sails and the second plurality of sails such that the firstplurality of sails rotate about the vertical axis while the secondplurality of sails and the external frame remain stationary.
 7. Themastless vertical axis wind turbine of claim 6, where the external framefurther comprises a plurality of legs disposed such that each of theplurality of legs converge above the first plurality of sails and thesecond plurality of sails at a central point about the vertical axis andsuch that each of the plurality of legs extend beyond a path swept bythe first plurality of sails during operation of the mastless verticalaxis wind turbine.
 8. The mastless vertical axis wind turbine of claim7, where the plurality of legs comprises three legs that are disposedsuch that each of the legs extends to a position that is radiallyseparated from positions to which the other two legs extend byapproximately 120 degrees.
 9. The mastless vertical axis wind turbine ofclaim 1, further comprising a generator in communication with theplatform and configured to generate energy in response to rotation ofthe platform.
 10. The mastless vertical axis wind turbine of claim 9,further comprising one or more energy storage units in communicationwith the generator.
 11. A method for generating energy utilizing amastless vertical axis wind turbine, the method comprising: configuringa first plurality of sails that during operation of the mastlessvertical axis wind turbine rotate about a vertical axis under theinfluence of wind; supporting the first plurality of sails utilizing aplatform that during operation of the mastless vertical axis windturbine is connected to and in tension with the first plurality of sailsat one or more points about a particular end of first the plurality ofthe sails; and configuring a second plurality of sails that duringoperation of the mastless vertical axis wind turbine remain stationaryas the first plurality of sails rotate under the influence of the wind,the second plurality of sails having respective first ends that arecoupled together and second ends that are each coupled to one or morestationary surfaces.
 12. The method of claim 11, where the secondplurality of sails includes four sails that are disposed such that eachsail of the second plurality of sails is disposed at a respectiveposition that is radially separated by approximately 90 degrees frompositions of adjacent sails of the second plurality of sails.
 13. Themethod of claim 11, where configuring the second plurality of sailsincludes disposing each of the second plurality of sails such that afirst axis that extends from a first side of the second end of the sailthrough a second side of the second end is oblique to a second axis thatextends from the center of the first plurality of sails through thesecond side of the second end.
 14. The method of claim 11, furthercomprising supporting the first plurality of sails and the secondplurality of sails utilizing an external frame that during operation ofthe mastless vertical axis wind turbine is coupled to and in tensionwith the first plurality of sails at one or more points about anopposite particular end of the first plurality of sails, where theexternal frame comprises a coupling mechanism that during operation ofthe mastless vertical axis wind turbine connects the external frame tothe first plurality of sails and the second plurality of sails such thatthe first plurality of sails rotate about the vertical axis while thesecond plurality of sails and the external frame remain stationary. 15.The method of claim 11, where the mastless vertical axis wind turbinefurther comprises a generator, in communication with the platform, thatgenerates energy in response to rotation of the platform.
 16. A mastlessvertical axis wind turbine, the mastless vertical axis wind turbinecomprising: a first plurality of sails configured to, during operationof the mastless vertical axis wind turbine, rotate about a vertical axisunder the influence of wind; a platform configured to couple the firstplurality of sails to a first stationary support, the platformconfigured to, during operation of the mastless vertical axis windturbine, be in tension with the first plurality of sails at one or morepoints about a first end of the first plurality of sails and to rotatewith the first plurality of sails under the influence of the wind, wherethe first stationary support is configured to remain stationary as thefirst plurality of sails rotate under the influence of the wind; asecond plurality of sails having respective first ends that are coupledtogether and second ends that are each coupled to one or more stationarysurfaces, the second plurality of sails configured to remain stationarywhile the first plurality of sails rotate under the influence of thewind; and a central connector configured to couple the first pluralityof sails and the second plurality of sails to a second stationarysupport, the central connector configured to, during operation of themastless vertical axis wind turbine, be in tension with the firstplurality of sails about the vertical axis and a second end of the firstplurality of sails.
 17. The mastless vertical axis wind turbine of claim16, where: the second plurality of sails includes four sails; and eachsail of the second plurality of sails is disposed at a respectiveposition that is radially separated by approximately 90 degrees frompositions of adjacent sails of the second plurality of sails.
 18. Themastless vertical axis wind turbine of claim 16, where a cross-sectionalarea of each of the second plurality of sails is greater than across-sectional area of each of the first plurality of sails.
 19. Themastless vertical axis wind turbine of claim 16, where, for each sail ofthe second plurality of sails, the sail is disposed such that a firstaxis that extends from a first side of the second end of the sailthrough a second side of the second end is oblique to a second axis thatextends from the center of the first plurality of sails through thesecond side of the second end.
 20. The mastless vertical axis windturbine of claim 19, where: the second plurality of sails includes foursails; and for each sail of the second plurality of sails, an acuteangle formed by an intersection of the first axis and the second axis isapproximately 30 degrees.
 21. The mastless vertical axis wind turbine ofclaim 16, where the platform comprises a plurality of spokes, where eachspoke of the plurality of spokes corresponds to a sail of the firstplurality of sails, and where each spoke of the plurality of spokesextends along a length of the first end of a corresponding sail of thefirst plurality of sails.
 22. The mastless vertical axis wind turbine ofclaim 21, where the plurality of spokes comprises six spokes in ahexagonal configuration, and where the first plurality of sailscomprises six sails.
 23. The mastless vertical axis wind turbine ofclaim 16, further comprising: a generator in communication with theplatform and centrally aligned with the vertical axis, the generatorconfigured to generate energy in response to rotation of the platform;and one or more energy storage units in communication with thegenerator.
 24. A method for generating energy utilizing a mastlessvertical axis wind turbine, the method comprising: engaging the mastlessvertical axis wind turbine with a first stationary support and a secondstationary support, where the mastless vertical axis wind turbinecomprises: a first plurality of sails that rotate about a vertical axisunder the influence of wind; a platform configured to couple the firstplurality of sails to the first stationary support, the platformconfigured to, during operation of the mastless vertical axis windturbine, be in tension with the first plurality of sails at one or morepoints about a first end of the first plurality of sails and to rotatewith the first plurality of sails under the influence of the wind whilethe first stationary support remains stationary; and a central connectorconfigured to couple the first plurality of sails to the secondstationary support, the central connector configured to, duringoperation of the mastless vertical axis wind turbine, be in tension withthe first plurality of sails about the vertical axis and a second end ofthe first plurality of sails; and engaging a second plurality of sailsto the central connector of the mastless vertical axis wind turbine, thesecond plurality of sails having respective first ends that are coupledtogether and second ends that are each coupled to one or more stationarysurfaces, the second plurality of sails configured to, during operationof the mastless vertical axis wind turbine, remain stationary while thefirst plurality of sails rotate under the influence of the wind.
 25. Themethod of claim 24, where the second plurality of sails includes foursails that are disposed such that each sail of the second plurality ofsails is disposed at a respective position that is radially separated byapproximately 90 degrees from positions of adjacent sails of the secondplurality of sails.
 26. The method of claim 24, where each of the secondplurality of sails are disposed such that a first axis that extends froma first side of the second end of the sail through a second side of thesecond end is oblique to a second axis that extends from the center ofthe first plurality of sails through the second side of the second end.